Commit Graph

2006 Commits

Author SHA1 Message Date
Andrew Morton
0a71220bc6 drivers/pci/intel-iommu.c: fix build with older gcc's
commit df08cdc7ef upstream.

drivers/pci/intel-iommu.c: In function `__iommu_calculate_agaw':
drivers/pci/intel-iommu.c:437: sorry, unimplemented: inlining failed in call to 'width_to_agaw': function body not available
drivers/pci/intel-iommu.c:445: sorry, unimplemented: called from here

Move the offending function (and its siblings) to top-of-file, remove the
forward declaration.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=17441

Reported-by: Martin Mokrejs <mmokrejs@ribosome.natur.cuni.cz>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-09-26 17:21:26 -07:00
Ben Hutchings
bd614669ff PCI: MSI: Restore read_msi_msg_desc(); add get_cached_msi_msg_desc()
commit 30da552428 upstream.

commit 2ca1af9aa3285c6a5f103ed31ad09f7399fc65d7 "PCI: MSI: Remove
unsafe and unnecessary hardware access" changed read_msi_msg_desc() to
return the last MSI message written instead of reading it from the
device, since it may be called while the device is in a reduced
power state.

However, the pSeries platform code really does need to read messages
from the device, since they are initially written by firmware.
Therefore:
- Restore the previous behaviour of read_msi_msg_desc()
- Add new functions get_cached_msi_msg{,_desc}() which return the
  last MSI message written
- Use the new functions where appropriate

Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-09-20 13:17:44 -07:00
Ben Hutchings
ed6fd21943 PCI: MSI: Remove unsafe and unnecessary hardware access
commit fcd097f31a upstream.

During suspend on an SMP system, {read,write}_msi_msg_desc() may be
called to mask and unmask interrupts on a device that is already in a
reduced power state.  At this point memory-mapped registers including
MSI-X tables are not accessible, and config space may not be fully
functional either.

While a device is in a reduced power state its interrupts are
effectively masked and its MSI(-X) state will be restored when it is
brought back to D0.  Therefore these functions can simply read and
write msi_desc::msg for devices not in D0.

Further, read_msi_msg_desc() should only ever be used to update a
previously written message, so it can always read msi_desc::msg
and never needs to touch the hardware.

Tested-by: "Michael Chan" <mchan@broadcom.com>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-09-20 13:17:44 -07:00
Tejun Heo
d2104f7940 PCI: disable MSI on VIA K8M800
commit 549e15611b upstream.

MSI delivery from on-board ahci controller doesn't work on K8M800.  At
this point, it's unclear whether the culprit is with the ahci
controller or the host bridge.  Given the track record and considering
the rather minimal impact of MSI, disabling it seems reasonable.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Rainer Hurtado Navarro <publio.escipion.el.africano@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-13 13:19:34 -07:00
Rafael J. Wysocki
9103169260 PCI: Do not run NVidia quirks related to MSI with MSI disabled
commit 3d2a531804 upstream.

There is no reason to run NVidia-specific quirks related to HT MSI
mappings with MSI disabled via pci=nomsi, so make
__nv_msi_ht_cap_quirk() return immediately in that case.

This allows at least one machine to boot 100% of the time with
pci=nomsi (it still doesn't boot reliably without that).

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=16443 .

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-13 13:19:33 -07:00
Michael S. Tsirkin
edc62dda41 virtio-pci: disable msi at startup
commit b03214d559 upstream.

virtio-pci resets the device at startup by writing to the status
register, but this does not clear the pci config space,
specifically msi enable status which affects register
layout.

This breaks things like kdump when they try to use e.g. virtio-blk.

Fix by forcing msi off at startup. Since pci.c already has
a routine to do this, we export and use it instead of duplicating code.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: linux-pci@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-08-02 10:20:42 -07:00
Tejun Heo
9b55bef26e ahci: add pci quirk for JMB362
commit 4daedcfe8c upstream.

JMB362 is a new variant of jmicron controller which is similar to
JMB360 but has two SATA ports instead of one.  As there is no PATA
port, single function AHCI mode can be used as in JMB360.  Add pci
quirk for JMB362.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Aries Lee <arieslee@jmicron.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-07-05 11:11:03 -07:00
Ben Hutchings
061d009690 PCI: Disable MSI for MCP55 on P5N32-E SLI
commit e4146bb908 upstream.

As reported in <http://bugs.debian.org/552299>, MSI appears to be
broken for this on-board device.  We already have a quirk for the
P5N32-SLI Premium; extend it to cover both variants of the board.

Reported-by: Romain DEGEZ <romain.degez@smartjog.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-07-05 11:10:41 -07:00
Alex Deucher
a4b1df4f95 PCI quirks: disable msi on AMD rs4xx internal gfx bridges
commit 9313ff4504 upstream.

Doesn't work reliably for internal gfx.  Fixes kernel bug
https://bugzilla.kernel.org/show_bug.cgi?id=15626.

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-07-05 11:10:40 -07:00
Matthew Wilcox
fbc6e1a622 PCI quirk: Disable MSI on VIA K8T890 systems
commit 134b345081 upstream.

Bugzilla 15287 indicates that there's a problem with Message Signalled
Interrupts on VIA K8T890 systems.  Add a quirk to disable MSI on these
systems.

Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Tested-by: Jan Kreuzer <kontrollator@gmx.de>
Tested-by: lh <jarryson@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-07-05 11:10:40 -07:00
Matthew Garrett
523273f08e PCI: Ensure we re-enable devices on resume
commit cc2893b6af upstream.

If the firmware puts a device back into D0 state at resume time, we'll
update its state in resume_noirq and thus skip the platform resume code.
Calling that code twice should be safe and we ought to avoid getting to
that point anyway, so remove the check and also allow the platform pci
code to be called for D0.

Fixes USB not being powered after resume on recent Lenovo machines.

Acked-by: Alex Chiang <achiang@canonical.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-12 14:57:12 -07:00
Andrew Patterson
90022a26dd PCI: fix nested spinlock hang in aer_inject
commit bd1f46deba upstream.

The aer_inject module hangs in aer_inject() when checking the device's
error masks.  The hang is due to a recursive use of the aer_inject lock.
The aer_inject() routine grabs the lock while processing the error and then
calls pci_read_config_dword to read the masks. The pci_read_config_dword
routine is earlier overridden by pci_read_aer, which among other things,
grabs the aer_inject lock.

Fixed by moving the pci_read_config_dword calls to read the masks to before
the lock is taken.

Acked-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: maximilian attems <max@stro.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-26 07:41:31 -07:00
Paul Mundt
892cb6dc64 PCI: kill off pci_register_set_vga_state() symbol export.
commit ded1d8f29b upstream.

When pci_register_set_vga_state() was made __init, the EXPORT_SYMBOL() was
retained, which now leaves us with a section mismatch.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: Mike Travis <travis@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: maximilian attems <max@stro.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-26 07:41:31 -07:00
Mike Travis
a6f2691c29 pci: Update pci_set_vga_state() to call arch functions
commit 95a8b6efc5 upstream.

Update pci_set_vga_state to call arch dependent functions to enable Legacy
VGA I/O transactions to be redirected to correct target.

[akpm@linux-foundation.org: make pci_register_set_vga_state() __init]
Signed-off-by: Mike Travis <travis@sgi.com>
LKML-Reference: <201002022238.o12McE1J018723@imap1.linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Robin Holt <holt@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: maximilian attems <max@stro.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-26 07:41:31 -07:00
Youquan Song
9623f6b42a PCIe AER: prevent AER injection if hardware masks error reporting
commit b49bfd3290 upstream.

The Correcteable/Uncorrectable Error Mask Registers are used by PCIe AER
driver which will controls the reporting of individual errors to PCIe RC
via PCIe error messages.

If hardware masks special error reporting to RC, the aer_inject driver
should not inject aer error.

Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Youquan Song <youquan.song@intel.com>
Acked-by: Ying Huang <ying.huang@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: maximilian attems <max@stro.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-26 07:41:30 -07:00
Dean Nelson
5aaccdbc12 PCI: cleanup error return for pcix get and set mmrbc functions
commit 7c9e2b1c47 upstream.

pcix_get_mmrbc() returns the maximum memory read byte count (mmrbc), if
successful, or an appropriate error value, if not.

Distinguishing errors from correct values and understanding the meaning of an
error can be somewhat confusing in that:

	correct values: 512, 1024, 2048, 4096
	errors: -EINVAL  			-22
 		PCIBIOS_FUNC_NOT_SUPPORTED	0x81
		PCIBIOS_BAD_VENDOR_ID		0x83
		PCIBIOS_DEVICE_NOT_FOUND	0x86
		PCIBIOS_BAD_REGISTER_NUMBER	0x87
		PCIBIOS_SET_FAILED		0x88
		PCIBIOS_BUFFER_TOO_SMALL	0x89

The PCIBIOS_ errors are returned from the PCI functions generated by the
PCI_OP_READ() and PCI_OP_WRITE() macros.

In a similar manner, pcix_set_mmrbc() also returns the PCIBIOS_ error values
returned from pci_read_config_[word|dword]() and pci_write_config_word().

Following pcix_get_max_mmrbc()'s example, the following patch simply returns
-EINVAL for all PCIBIOS_ errors encountered by pcix_get_mmrbc(), and -EINVAL
or -EIO for those encountered by pcix_set_mmrbc().

This simplification was chosen in light of the fact that none of the current
callers of these functions are interested in the specific type of error
encountered. In the future, should this change, one could simply create a
function that maps each PCIBIOS_ error to a corresponding unique errno value,
which could be called by pcix_get_max_mmrbc(), pcix_get_mmrbc(), and
pcix_set_mmrbc().

Additionally, this patch eliminates some unnecessary variables.

Signed-off-by: Dean Nelson <dnelson@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01 15:58:45 -07:00
Dean Nelson
d548d479f2 PCI: fix access of PCI_X_CMD by pcix get and set mmrbc functions
commit bdc2bda7c4 upstream.

An e1000 driver on a system with a PCI-X bus was always being returned
a value of 135 from both pcix_get_mmrbc() and pcix_set_mmrbc(). This
value reflects an error return of PCIBIOS_BAD_REGISTER_NUMBER from
pci_bus_read_config_dword(,, cap + PCI_X_CMD,).

This is because for a dword, the following portion of the PCI_OP_READ()
macro:

	if (PCI_##size##_BAD) return PCIBIOS_BAD_REGISTER_NUMBER;

expands to:

	if (pos & 3) return PCIBIOS_BAD_REGISTER_NUMBER;

And is always true for 'cap + PCI_X_CMD', which is 0xe4 + 2 = 0xe6. ('cap' is
the result of calling pci_find_capability(, PCI_CAP_ID_PCIX).)

The same problem exists for pci_bus_write_config_dword(,, cap + PCI_X_CMD,).
In both cases, instead of calling _dword(), _word() should be called.

Signed-off-by: Dean Nelson <dnelson@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01 15:58:45 -07:00
Dean Nelson
aa6760432a PCI: fix return value from pcix_get_max_mmrbc()
commit 25daeb550b upstream.

For the PCI_X_STATUS register, pcix_get_max_mmrbc() is returning an incorrect
value, which is based on:

	(stat & PCI_X_STATUS_MAX_READ) >> 12

Valid return values are 512, 1024, 2048, 4096, which correspond to a 'stat'
(masked and right shifted by 21) of 0, 1, 2, 3, respectively.

A right shift by 11 would generate the correct return value when 'stat' (masked
and right shifted by 21) has a value of 1 or 2. But for a value of 0 or 3 it's
not possible to generate the correct return value by only right shifting.

Fix is based on pcix_get_mmrbc()'s similar dealings with the PCI_X_CMD register.

Signed-off-by: Dean Nelson <dnelson@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01 15:58:44 -07:00
Alexander Duyck
81aa42727e pci: add support for 82576NS serdes to existing SR-IOV quirk
commit 7a0deb6bcd upstream.

This patch adds support for the 82576NS Serdes adapter to the existing pci
quirk for 82576 parts.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01 15:58:15 -07:00
Andrew Patterson
1ebf19e8a1 PCI: unconditionally clear AER uncorr status register during cleanup
commit 6cdfd995a6 upstream.

The current implementation of pci_cleanup_aer_uncorrect_error_status
only clears either fatal or non-fatal error status bits depending
on the state of the I/O channel. This implementation will then often
leave some bits set after PCI error recovery completes.  The uncleared bit
settings will then be falsely reported the next time an AER interrupt is
generated for that hierarchy. An easy way to illustrate this issue is to
use the aer-inject module to simultaneously inject both an uncorrectable
non-fatal and uncorrectable fatal error.  One of the errors will not be
cleared.

This patch resolves this issue by unconditionally clearing all bits in
the AER uncorrectable status register. All settings and corrective action
strategies are saved and determined before
pci_cleanup_aer_uncorrect_error_status is called, so this change should not
affect errory handling functionality.

Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Alex Chiang <achiang@hp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-01 15:58:12 -07:00
Andrew Morton
3cf2600e7e PCI hotplug: check ioremap() return value in ibmphp_ebda.c
commit ba02b242bb upstream.

check ioremap() return value.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-15 08:49:35 -07:00
Chandru
7bc9597fec PCI hotplug: ibmphp: read the length of ebda and map entire ebda region
commit b0fc889c43 upstream.

ibmphp driver currently maps only 1KB of ebda memory area into kernel address
space during driver initialization. This causes kernel oops when the driver is
modprobe'd and it accesses memory beyond 1KB within ebda segment. The first
byte of ebda segment actually stores the length of the ebda region in
Kilobytes. Hence make use of the length parameter and map the entire ebda
region.

Signed-off-by: Chandru Siddalingappa <chandru@linux.vnet.ibm.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-15 08:49:35 -07:00
Song Youquan
5172b4b0f1 PCI: AER: fix aer inject result in kernel oops
commit 46256f83d0 upstream.

If the BIOS does not export _OSC to allow OS take over the PCIe AER, the
pcie aer driver will not initialize the aer service. However, the
aer_inject driver does not check this scenario, which results in a kernel
oops when injecting an aer error into OS.  For example:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000350
IP: [<ffffffff812e08f7>] _spin_lock_irqsave+0xc/0x23
PGD 155c41067 PUD 157fe0067 PMD 0
Oops: 0002 [#1] SMP
Pid: 5119, comm: aer-inject Not tainted 2.6.32-rc8-mce #2
RIP: 0010:[<ffffffff812e08f7>]  [<ffffffff812e08f7>] _spin_lock_irqsave+0xc/0x23
RSP: 0018:ffff880157f81e28  EFLAGS: 00010096
RAX: 0000000000000296 RBX: 0000000000000000 RCX: 0000000000000100
RDX: 0000000000010000 RSI: 0000000000000246 RDI: 0000000000000350
RBP: ffff880157f81e28 R08: 0000000000000004 R09: ffff880157f81dac
R10: ffff88015a666f60 R11: ffff88015a666f40 R12: ffff88015758cc00
R13: 0000000000000350 R14: 0000000000000000 R15: 0000000000000100
FS:  00007f4d4a66e6f0(0000) GS:ffff8800282e0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000350 CR3: 000000015661a000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process aer-inject (pid: 5119, threadinfo ffff880157f80000, task ffff8801585f4340)
Stack:
 ffff880157f81e78 ffffffff811b1615 ffff880157f81e78 ffffffff81222823
Call Trace:
 [<ffffffff811b1615>] aer_irq+0x38/0x117
 [<ffffffff81222823>] ? device_for_each_child+0x5f/0x6f
 [<ffffffffa00967bf>] aer_inject_write+0x409/0x45e [aer_inject]
 [<ffffffff810eb80e>] vfs_write+0xae/0x16a
 [<ffffffff810eb98e>] sys_write+0x47/0x6e
 [<ffffffff8100ba2b>] system_call_fastpath+0x16/0x1b
RIP  [<ffffffff812e08f7>] _spin_lock_irqsave+0xc/0x23
 RSP <ffff880157f81e28>
CR2: 0000000000000350

So check the _OSC before assuming that AER is available to the OS.

Signed-off-by: Song Youquan <youquan.song@intel.com>
Acked-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-28 15:01:51 -08:00
Alex Williamson
83886fa2a0 PCI: Always set prefetchable base/limit upper32 registers
commit 59353ea30e upstream.

Prior to 1f82de10 we always initialized the upper 32bits of the
prefetchable memory window, regardless of the address range used.
Now we only touch it for a >32bit address, which means the upper32
registers remain whatever the BIOS initialized them too.

It's valid for the BIOS to set the upper32 base/limit to
0xffffffff/0x00000000, which makes us program prefetchable ranges
like 0xffffffffabc00000 - 0x00000000abc00000

Revert the chunk of 1f82de10 that made this conditional so we always
write the upper32 registers and remove now unused pref_mem64 variable.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Rafael J. Wysocki <rjw@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-28 15:01:15 -08:00
Benjamin Herrenschmidt
2db740cb36 PCI/cardbus: Add a fixup hook and fix powerpc
commit 2d1c861871 upstream

The cardbus code creates PCI devices without ever going through the
necessary fixup bits and pieces that normal PCI devices go through.

There's in fact a commented out call to pcibios_fixup_bus() in there,
it's commented because ... it doesn't work.

I could make pcibios_fixup_bus() do the right thing on powerpc easily
but I felt it cleaner instead to provide a specific hook pci_fixup_cardbus
for which a weak empty implementation is provided by the PCI core.

This fixes cardbus on powerbooks and probably all other PowerPC
platforms which was broken completely for ever on some platforms and
since 2.6.31 on others such as PowerBooks when we made the DMA ops
mandatory (since those are setup by the fixups).

Acked-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-22 15:18:26 -08:00
Chris Wright
acb724d43a intel-iommu: ignore page table validation in pass through mode
commit 1672af1164 upstream.

We are seeing a bug when booting w/ iommu=pt with current upstream
(bisect blames 19943b0e30 "intel-iommu:
Unify hardware and software passthrough support).

The issue is specific to this loop during identity map initialization
of each device:

domain_context_mapping_one(si_domain, ..., CONTEXT_TT_PASS_THROUGH)
...
		/* Skip top levels of page tables for
		* iommu which has less agaw than default.
		*/
		for (agaw = domain->agaw; agaw != iommu->agaw; agaw--) {
			pgd = phys_to_virt(dma_pte_addr(pgd));
			if (!dma_pte_present(pgd)) {      <------ failing here
				spin_unlock_irqrestore(&iommu->lock, flags);
			return -ENOMEM;
		}

This box has 2 iommu's in it.  The catchall iommu has MGAW == 48, and
SAGAW == 4.  The other iommu has MGAW == 39, SAGAW == 2.

The device that's failing the above pgd test is the only device connected
to the non-catchall iommu, which has a smaller address width than the
domain default.  This test is not necessary since the context is in PT
mode and the ASR is ignored.

Thanks to Don Dutile for discovering and debugging this one.

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-18 14:05:59 -08:00
David Woodhouse
020d1eecf3 intel-iommu: Fix oops with intel_iommu=igfx_off
commit 44cd613c0e upstream.

The hotplug notifier will call find_domain() to see if the device in
question has been assigned an IOMMU domain. However, this should never
be called for devices with a "dummy" domain, such as graphics devices
when intel_iommu=igfx_off is set and the corresponding IOMMU isn't even
initialised. If you do that, it'll oops as it dereferences the (-1)
pointer.

The notifier function should check iommu_no_mapping() for the
device before doing anything else.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-18 14:05:57 -08:00
David Woodhouse
39035f9c09 intel-iommu: Check for an RMRR which ends before it starts.
commit 5595b528b4 upstream.

Some HP BIOSes report an RMRR region (a region which needs a 1:1 mapping
in the IOMMU for a given device) which has an end address lower than its
start address. Detect that and warn, rather than triggering the
BUG() in dma_pte_clear_range().

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-18 14:05:55 -08:00
David Woodhouse
b02375be25 intel-iommu: Apply BIOS sanity checks for interrupt remapping too.
commit 6ecbf01c7c upstream.

The BIOS errors where an IOMMU is reported either at zero or a bogus
address are causing problems even when the IOMMU is disabled -- because
interrupt remapping uses the same hardware. Ensure that the checks get
applied for the interrupt remapping initialisation too.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-18 14:05:54 -08:00
Chris Wright
518cdfa0f6 intel-iommu: Detect DMAR in hyperspace at probe time.
commit 2c99220810 upstream.

Many BIOSes will lie to us about the existence of an IOMMU, and claim
that there is one at an address which actually returns all 0xFF.

We need to detect this early, so that we know we don't have a viable
IOMMU and can set up swiotlb before it's too late.

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-18 14:05:53 -08:00
David Woodhouse
5854d9c8d1 Fix handling of the HP/Acer 'DMAR at zero' BIOS error for machines with <4GiB RAM.
Commit 86cf898e1d ("intel-iommu: Check for
'DMAR at zero' BIOS error earlier.") was supposed to work by pretending
not to detect an IOMMU if it was actually being reported by the BIOS at
physical address zero.

However, the intel_iommu_init() function is called unconditionally, as
are the corresponding functions for other IOMMU hardware.

So the patch only worked if you have RAM above the 4GiB boundary. It
caused swiotlb to be initialised when no IOMMU was detected during early
boot, and thus the later IOMMU init would refuse to run.

But if you have less RAM than that, swiotlb wouldn't get set up and the
IOMMU _would_ still end up being initialised, even though we never
claimed to detect it.

This patch also sets the dmar_disabled flag when the error is detected
during the initial detection phase -- so that the later call to
intel_iommu_init() will return without doing anything, regardless of
whether swiotlb is used or not.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-19 13:42:02 -08:00
Linus Torvalds
a9366e61b0 Merge git://git.infradead.org/users/dwmw2/iommu-2.6.32
* git://git.infradead.org/users/dwmw2/iommu-2.6.32:
  intel-iommu: Support PCIe hot-plug
  intel-iommu: Obey coherent_dma_mask for alloc_coherent on passthrough
  intel-iommu: Check for 'DMAR at zero' BIOS error earlier.
2009-11-14 13:05:27 -08:00
Fenghua Yu
99dcadede4 intel-iommu: Support PCIe hot-plug
To support PCIe hot plug in IOMMU, we register a notifier to respond to device
change action.

When the notifier gets BUS_NOTIFY_UNBOUND_DRIVER, it removes the device
from its DMAR domain.

A hot added device will be added into an IOMMU domain when it first does IOMMU
op. So there is no need to add more code for hot add.

Without the patch, after a hot-remove, a hot-added device on the same
slot will not work.

Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Tested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-11-12 02:28:45 +00:00
Alex Williamson
e8bb910d1b intel-iommu: Obey coherent_dma_mask for alloc_coherent on passthrough
The model for IOMMU passthrough is that decent devices that can cope
with DMA to all of memory get passthrough; crappy devices with a limited
dma_mask don't -- they get to use the IOMMU anyway.

This is done on the basis that IOMMU passthrough is usually wanted for
performance reasons, and it's only the decent PCI devices that you
really care about performance for, while the crappy 32-bit ones like
your USB controller can just use the IOMMU and you won't really care.

Unfortunately, the check for this was only looking at dev->dma_mask, not
at dev->coherent_dma_mask. And some devices have a 32-bit
coherent_dma_mask even though they have a full 64-bit dma_mask.

Even more unfortunately, fixing that simple oversight would upset
certain broken HP devices. Not only do they have a 32-bit
coherent_dma_mask, but they also have a tendency to do stray DMA to
unmapped addresses. And then they die when they take the DMA fault they
so richly deserve.

So if we do the 'correct' fix, it'll mean that affected users have to
disable IOMMU support completely on "a large percentage of servers from
a major vendor."

Personally, I have little sympathy -- given that this is the _same_
'major vendor' who is shipping machines which claim to have IOMMU
support but have obviously never _once_ booted a VT-d capable OS to do
any form of QA. But strictly speaking, it _would_ be a regression even
though it only ever worked by fluke.

For 2.6.33, we'll come up with a quirk which gives swiotlb support
for this particular device, and other devices with an inadequate
coherent_dma_mask will just get normal IOMMU mapping.

The simplest fix for 2.6.32, though, is just to jump through some hoops
to try to allocate coherent DMA memory for such devices in a place that
they can reach. We'd use dma_generic_alloc_coherent() for this if it
existed on IA64.

Signed-off-by: Alex Williamson <alex.williamson@hp.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-11-12 02:10:34 +00:00
David Woodhouse
86cf898e1d intel-iommu: Check for 'DMAR at zero' BIOS error earlier.
Chris Wright has some patches which let us fall back to swiotlb nicely
if IOMMU initialisation fails. But those are a bit much for 2.6.32.

Instead, let's shift the check for the biggest problem, the HP and Acer
BIOS bug which reports a DMAR at physical address zero. That one can
actually be checked much earlier -- before we even admit to having
detected an IOMMU in the first place. So the swiotlb init goes ahead as
we want.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-11-09 22:15:15 +00:00
Kenji Kaneshige
761434a318 PCI ASPM: fix oops on root port removal
Fix the following BUG_ON() problem reported by Alex Chiang.

This problem happened when removing PCIe root port using PCI logical
hotplug operation.

The immediate cause of this problem is that the pointer to invalid
data structure is passed to pcie_update_aspm_capable() by
pcie_aspm_exit_link_state(). When pcie_aspm_exit_link_state() received
a pointer to root port link, it unconfigures the root port link and
frees its data structure at first. At this point, there are not links
to configure under the root port and the data structure for root port
link is already freed. So pcie_aspm_exit_link_state() must not call
pcie_update_aspm_capable() and pcie_config_aspm_path().

This patch fixes the problem by changing pcie_aspm_exit_link_state()
not to call pcie_update_aspm_capable() and pcie_config_aspm_path() if
the specified link is root port link.

------------[ cut here ]------------
kernel BUG at drivers/pci/pcie/aspm.c:606!
invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
last sysfs file: /sys/devices/pci0000:40/0000:40:13.0/remove
CPU 1
Modules linked in: shpchp
Pid: 9345, comm: sysfsd Not tainted 2.6.32-rc5 #98 ProLiant DL785 G6
RIP: 0010:[<ffffffff811df69b>]  [<ffffffff811df69b>] pcie_update_aspm_capable+0x15/0xbe
RSP: 0018:ffff88082a2f5ca0  EFLAGS: 00010202
RAX: 0000000000000e77 RBX: ffff88182cc3e000 RCX: ffff88082a33d006
RDX: 0000000000000001 RSI: ffffffff811dff4a RDI: ffff88182cc3e000
RBP: ffff88082a2f5cc0 R08: ffff88182cc3e000 R09: 0000000000000000
R10: ffff88182fc00180 R11: ffff88182fc00198 R12: ffff88182cc3e000
R13: 0000000000000000 R14: ffff88182cc3e000 R15: ffff88082a2f5e20
FS:  00007f259a64b6f0(0000) GS:ffff880864600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 00007feb53f73da0 CR3: 000000102cc94000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process sysfsd (pid: 9345, threadinfo ffff88082a2f4000, task ffff88082a33cf00)
Stack:
 ffff88182cc3e000 ffff88182cc3e000 0000000000000000 ffff88082a33cf00
<0> ffff88082a2f5cf0 ffffffff811dff52 ffff88082a2f5cf0 ffff88082c525168
<0> ffff88402c9fd2f8 ffff88402c9fd2f8 ffff88082a2f5d20 ffffffff811d7db2
Call Trace:
 [<ffffffff811dff52>] pcie_aspm_exit_link_state+0xf5/0x11e
 [<ffffffff811d7db2>] pci_stop_bus_device+0x76/0x7e
 [<ffffffff811d7d67>] pci_stop_bus_device+0x2b/0x7e
 [<ffffffff811d7e4f>] pci_remove_bus_device+0x15/0xb9
 [<ffffffff811dcb8c>] remove_callback+0x29/0x3a
 [<ffffffff81135aeb>] sysfs_schedule_callback_work+0x15/0x6d
 [<ffffffff81072790>] worker_thread+0x19d/0x298
 [<ffffffff8107273b>] ? worker_thread+0x148/0x298
 [<ffffffff81135ad6>] ? sysfs_schedule_callback_work+0x0/0x6d
 [<ffffffff810765c0>] ? autoremove_wake_function+0x0/0x38
 [<ffffffff810725f3>] ? worker_thread+0x0/0x298
 [<ffffffff8107629e>] kthread+0x7d/0x85
 [<ffffffff8102eafa>] child_rip+0xa/0x20
 [<ffffffff8102e4bc>] ? restore_args+0x0/0x30
 [<ffffffff81076221>] ? kthread+0x0/0x85
 [<ffffffff8102eaf0>] ? child_rip+0x0/0x20
Code: 89 e5 8a 50 48 31 c0 c0 ea 03 83 e2 07 e8 b2 de fe ff c9 48 98 c3 55 48 89 e5 41 56 49 89 fe 41 55 41 54 53 48 83 7f 10 00 74 04 <0f> 0b eb fe 48 8b 05 da 7d 63 00 4c 8d 60 e8 4c 89 e1 eb 24 4c
RIP  [<ffffffff811df69b>] pcie_update_aspm_capable+0x15/0xbe
 RSP <ffff88082a2f5ca0>
---[ end trace 6ae0f65bdeab8555 ]---

Reported-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-11-06 14:01:23 -08:00
Jesse Barnes
55a1098476 Revert "PCI: get larger bridge ranges when space is available"
This reverts commit 308cf8e13f.  This
patch had trouble with transparent bridges, among other things.  A more
readable and correct version should land in 2.6.33.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-27 09:39:18 -07:00
Shane Huang
5deab53665 ahci / atiixp / pci quirks: rename AMD SB900 into Hudson-2
This patch renames the code name SB900 into Hudson-2

Signed-off-by: Shane Huang <shane.huang@amd.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-10-16 06:21:20 -04:00
Ingo Molnar
86ae13b006 headers: Fix build after <linux/sched.h> removal
Commit d43c36dc6b ("headers: remove
sched.h from interrupt.h") left some build errors in some configurations
due to drivers having depended on getting header files "accidentally".

Signed-off-by: Ingo Molnar <mingo@elte.hu>
[ Combined several one-liners from Ingo into one single patch  - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-13 10:20:16 -07:00
Linus Torvalds
80fa680d22 Merge git://git.infradead.org/~dwmw2/iommu-2.6.32
* git://git.infradead.org/~dwmw2/iommu-2.6.32:
  x86: Move pci_iommu_init to rootfs_initcall()
  Run pci_apply_final_quirks() sooner.
  Mark pci_apply_final_quirks() __init rather than __devinit
  Rename pci_init() to pci_apply_final_quirks(), move it to quirks.c
  intel-iommu: Yet another BIOS workaround: Isoch DMAR unit with no TLB space
  intel-iommu: Decode (and ignore) RHSA entries
  intel-iommu: Make "Unknown DMAR structure" message more informative
2009-10-13 10:04:40 -07:00
Linus Torvalds
2caa731819 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: Prevent AER driver from being loaded on non-root port PCIE devices
  PCI: get larger bridge ranges when space is available
  PCI: pci.c: fix kernel-doc notation
  PCI quirk: TI XIO200a erroneously reports support for fast b2b transfers
  PCI PM: Read device power state from register after updating it
  PCI: remove pci_assign_resource_fixed()
  PCI: PCIe portdrv: remove "-driver" from driver name
2009-10-12 14:38:34 -07:00
David Woodhouse
cf6f3bf7e5 Run pci_apply_final_quirks() sooner.
Having this as a device_initcall() means that some real device drivers
can actually initialise _before_ the quirks are run, which is wrong.

We want it to run _before_ device_initcall(), but _after_ fs_initcall(),
since some arch-specific PCI initialisation like pcibios_assign_resources()
is done at fs_initcall().

We could use rootfs_initcall() but I actually want to use that for the
IOMMU initialisation, which has to come after the quirks, but still
before the real devices. So use fs_initcall_sync() instead -- since this
is entirely synchronous, it doesn't hurt that it'll escape the
synchronisation.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-10-12 14:42:09 +01:00
David Woodhouse
0001026884 Mark pci_apply_final_quirks() __init rather than __devinit
It doesn't get invoked on hotplug; it can be thrown away after init.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-10-12 14:42:06 +01:00
David Woodhouse
8d86fb2c80 Rename pci_init() to pci_apply_final_quirks(), move it to quirks.c
This function may have done more in the past, but all it does now is
apply the PCI_FIXUP_FINAL quirks. So name it sensibly and put it where
it belongs.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2009-10-12 14:42:04 +01:00
Alexey Dobriyan
d43c36dc6b headers: remove sched.h from interrupt.h
After m68k's task_thread_info() doesn't refer to current,
it's possible to remove sched.h from interrupt.h and not break m68k!
Many thanks to Heiko Carstens for allowing this.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-10-11 11:20:58 -07:00
Kenji Kaneshige
30fc24b5cb PCI: Prevent AER driver from being loaded on non-root port PCIE devices
A bug was seen on boards using a PLX 8518 switch device which advertises
AER on each of it's transparent bridges. The AER driver was loaded for
each bridge and this driver tried to access the AER source ID register
whenever an interrupt occured on the shared PCI INTX lines. The source
ID register does not exist on non root port PCIE device's  which
advertise AER and trying to access this register causes a unsupported
request error on the bridge. Thus, when the next interrupt occurs,
another error is found and the non existent source ID register is
accessed again, and so it goes on.

The result is a spammed dmesg with unsupported request PCI express
errors on the bridge device that the AER driver is loaded against.

Reported-by: Malcolm Crossley <malcolm.crossley2@gefanuc.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Tested-by: Malcolm Crossley <malcolm.crossley2@gefanuc.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 09:28:56 -07:00
Yinghai Lu
308cf8e13f PCI: get larger bridge ranges when space is available
Found one system:
[   71.120590] pci 0000:40:05.0: scanning behind bridge, config 4f4a40, pass 0
[   71.138283] PCI: Scanning bus 0000:4a
[   71.140341] pci 0000:4a:00.0: found [15b3:6278] class 000c06 header type 00
[   71.157173] pci 0000:4a:00.0: reg 10 64bit mmio: [0x000000-0x0fffff]
[   71.161697] pci 0000:4a:00.0: reg 18 64bit mmio pref: [0x000000-0x7fffff]
[   71.179403] pci 0000:4a:00.0: reg 20 64bit mmio pref: [0x000000-0xfffffff]
[   71.185366] pci 0000:4a:00.0: calling quirk_resource_alignment+0x0/0x1dd
[   71.200846] pci 0000:4a:00.0: disabling ASPM on pre-1.1 PCIe device.  You can enable it with 'pcie_aspm=force'
[   71.219623] PCI: Fixups for bus 0000:4a
[   71.222194] pci 0000:40:05.0: bridge 32bit mmio: [0xcf000000-0xcf0fffff]
[   71.238662] pci 0000:40:05.0: bridge 64bit mmio pref: [0xcd800000-0xcdffffff]
[   71.255793] PCI: Bus scan for 0000:4a returning with max=4a

Device needs a big pref mmio, but BIOS doesn't allocate mmio to it aside
from a small MMIO range.  Later, the kernel will not allocate resources to
that to the device:
[   99.574030] pci 0000:4a:00.0: BAR 4: can't allocate mem resource [0xd0000000-0xcdffffff]
[   99.580102] pci 0000:4a:00.0: BAR 2: got res [0xcd800000-0xcdffffff] bus [0xcd800000-0xcdffffff] flags 0x12120c
[   99.602307] pci 0000:4a:00.0: BAR 2: moved to bus [0xcd800000-0xcdffffff] flags 0x12120c
[   99.615991] pci 0000:4a:00.0: BAR 0: got res [0xcf000000-0xcf0fffff] bus [0xcf000000-0xcf0fffff] flags 0x120204
[   99.634499] pci 0000:4a:00.0: BAR 0: moved to bus [0xcf000000-0xcf0fffff] flags 0x120204
[   99.654318] pci 0000:40:05.0: PCI bridge, secondary bus 0000:4a
[   99.658766] pci 0000:40:05.0:   IO window: disabled
[   99.675478] pci 0000:40:05.0:   MEM window: 0xcf000000-0xcf0fffff
[   99.681663] pci 0000:40:05.0:   PREFETCH window: 0x000000cd800000-0x000000cdffffff

So try to get a big range in the pci bridge if there is no child using
that range.  With the patch we get:
[   99.104525] pci 0000:4a:00.0: BAR 4: got res [0xfc080000000-0xfc08fffffff] bus [0xfc080000000-0xfc08fffffff] flags 0x12120c
[   99.123624] pci 0000:4a:00.0: BAR 4: moved to bus [0xfc080000000-0xfc08fffffff] flags 0x12120c
[   99.131977] pci 0000:4a:00.0: BAR 2: got res [0xfc090000000-0xfc0907fffff] bus [0xfc090000000-0xfc0907fffff] flags 0x12120c
[   99.149788] pci 0000:4a:00.0: BAR 2: moved to bus [0xfc090000000-0xfc0907fffff] flags 0x12120c
[   99.169248] pci 0000:4a:00.0: BAR 0: got res [0xc0200000-0xc02fffff] bus [0xc0200000-0xc02fffff] flags 0x120204
[   99.189508] pci 0000:4a:00.0: BAR 0: moved to bus [0xc0200000-0xc02fffff] flags 0x120204
[   99.206402] pci 0000:40:05.0: PCI bridge, secondary bus 0000:4a
[   99.210637] pci 0000:40:05.0:   IO window: disabled
[   99.224856] pci 0000:40:05.0:   MEM window: 0xc0200000-0xc03fffff
[   99.230019] pci 0000:40:05.0:   PREFETCH window: 0x000fc080000000-0x000fc097ffffff

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 09:28:18 -07:00
Randy Dunlap
19eea630f7 PCI: pci.c: fix kernel-doc notation
Fix kernel-doc notation (& warnings) in pci/pci.c.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 09:28:18 -07:00
Gabe Black
1f56f4a2b4 PCI quirk: TI XIO200a erroneously reports support for fast b2b transfers
This quirk will disable fast back to back transfer on the secondary bus
segment of the TI Bridge.

Signed-off-by: Gabe Black <gabe.black@ni.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-07 09:28:17 -07:00
Rafael J. Wysocki
e13cdbd71f PCI PM: Read device power state from register after updating it
After attempting to change the power state of a PCI device
pci_raw_set_power_state() doesn't check if the value it wrote into
the device's PCI_PM_CTRL register has been stored in there, but
unconditionally modifies the device's current_state field to reflect
the change.  This may cause problems to happen if the power state of
the device hasn't been changed in fact, because it will make the PCI
PM core make a wrong assumption.

To prevent such situations from happening modify
pci_raw_set_power_state() so that it reads the device's PCI_PM_CTRL
register after writing into it and uses the value read from the
register to update the device's current_state field.  Also make it
print a message saying that the device refused to change its power
state as requested (returning an error code in such cases would cause
suspend regressions to appear on some systems, where device drivers'
suspend routines return error codes if pci_set_power_state() fails).

Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-10-06 10:27:51 -07:00